Earlier this year, Echo, the well-loved elephant matriarch in Kenya's Amboseli National Park, died at the ripe old age of 64. For decades, my colleagues and I in the Amboseli Elephant Research Project had watched her lead her family around the park and the surrounding ecosystem as they encountered the enriching variety of their life: finding food amid the grasses, bushes and trees; meeting, greeting, and interacting with hundreds of other elephants; resting under shade trees; drinking from rivers and pools; wallowing in mud and dust baths.

When it came to measuring movement, our observation records and radio-tracking showed Echo to be the most conservative of the Amboseli elephants. With a dry season range of around 50 square miles in the area around the National Park swamps, she moved in smaller circles than most of the population. But every time it rained, she would head off for the verdant bush lands, joining other families and independent bulls to range across a much wider area covering hundreds of square miles. When food and water is abundant, wild elephants clearly revel in their unconstrained freedom to roam.

Recent articles on elephants at the North Carolina Zoo (by Doug Clark, Sept. 16, and David Jones, Sept. 27) illustrate just how far the keeping of elephants in captivity diverges from what they need naturally.

Does the size of its living area really matter to an elephant? It is easy to discover from published results and summaries on the N.C. Zoo's own Web site that their collaborative studies in Cameroon show individual elephants using home ranges from hundreds to more than 2,000 square kilometers (770 square miles, or half the size of Rhode Island) in size.

These results echo our research in Amboseli and studies from all over Africa and Asia: Elephants in the wild do not live in anything like the tiny diorama-style patches of land in even the most "modern" zoo exhibit. They live in extensive areas and use them fully, to socialize, find mates and "friends," explore and forage, not to stand around in a display for visitors to observe for a few minutes before moving on to the next attraction.

Elephants that are free to move are also free from the painful and life-threatening joint and foot problems, not to mention the bored, stereotypical swaying and head-bobbing behavior, so often seen in confined animals. So, providing adequate space is good preventative medicine, saving money that would otherwise be spent on expensive veterinary treatments for ailments the zoo environment itself causes, as well as averting misery or premature death.

Rather than seeking to discover and provide the best living conditions from their elephants' point of view, zoos instead make it their priority to entertain (and, they claim, educate) fee-paying customers. Zoos are too often willing to sacrifice elephant well-being as a trade-off for the practicalities of running a public display in the competitive entertainment business.

N.C. Zoo Director Dr. David Jones argues that large enclosures make it harder for visitors to see elephants. If the best interests of the elephants were a priority, these animals would not be kept in confined conditions simply to force them closer to the audience. Plenty of creative alternatives exist to bring the audience closer to the animals. These could include trams and walkways through elephant habitat or locating viewing hides where elephants gather at water holes or shade trees. Zoos could also deploy the same technology used routinely in (for example) stadium concerts, such as CCTV and large format monitors, to give up-close and personal views.

The N.C. Zoo also contends that providing space for elephants on the scale appropriate to their great size is too expensive, and small enclosures must suffice. This is true in most urban zoos because land prices, rents and taxes are very high in cities. But the N.C. Zoo is in a rural area where it is possible to have the wide-open spaces elephants really need. If the zoo cannot afford to give elephants this kind of environment, then the humane option is not to shrug and accept the trade-off in living standards, but to ask whether it is right to keep them at all.

Zoos say they want to continue keeping elephants in the current unacceptable conditions for another 10-15 years, while they do their own research into welfare standards. But surely we know enough already: Elephants are clearly evolved for walking, a lot of walking. When they have good, rich environments to move around in, on the order of square miles, not acres, they are healthy and happy. When they are confined to a few sterile acres or less, they inevitably suffer.

It is time for zoo officials to step outside their closed world and acknowledge the abundant evidence from field studies and sanctuary experience that shows the key to well-being in elephants is the room to move.

Keith Lindsay is a Canadian conservation biologist and environmental consultant now based in Oxford, with more than 30 years' experience in biodiversity research and conservation, natural resource sustainability and social development in Africa, Asia, the Middle East, the Caribbean and Canada.